Surround and Sub advice sought

Have read an overwhelming amount of material on this site and others. First post. Thanks in advance to all responders. soliciting comments on surrounds and subs. HT/music 50/50. both important. No classical, no jazz. Rock, alternative, dance. Marantz 7008. Room: open concept (giant shoebox) family room and kitchen 17x 37 with 20' ceiling for 19ft from front wall. Then 10ft ceiling remaining 18ft to back wall. IOW there is a back wall 19ft from front wall but it starts at 10ft off floor and then there is the second back wall at 37ft from front. seating 13ft from front speakers which are on front 17ft wide wall and set 9ft apart. Floor: cork. Pretty much set on 35xt for front (heard 'em, love 'em). no center now (seating is in center of room; probably not needed based on audition of 35xt; rather spend $ elsewhere for now). due to room configuration surrounds have to be mounted on side walls at about 10 ft high and they gotta be white. That means Motion4, Motion FX or Motion 15? surrounds could go in corner at "first" back wall or on back wall as rears, but then they would be 15ft behind seating. for sub, thinking one or two dynamo 1500 or one BF210. open to other subs such as paradigm (still can use pbk) or svs. Again, thanks for comments.